Rotor for a roll crusher

ABSTRACT

A peripheral crushing element is held in a dovetailed groove of a rotor by a prismatic wedge member which is interposed between one face of the crushing element and the tapering wall of the groove. The wedge member extends the length of the crushing element and has opposite walls in abutting engagement with the crushing element face and the groove wall, respectively. A key locks the wedge member to the crushing element into a unit for joint movement in an outward direction.

PM Fei. 29, |972 3,645,459

2 Shana-Sheet 1 lNveN'roRs. ROBERT LUCAS JEAN PIERRE MILL/ER BY FlZ AGENT 'PM nl. 29, 1912 3,645,459

2 Shouts-Shoot 2 /NvffNf/o/es. ROBERT LUGAS .JEAN PIERRE MILL/ER BY 1,' 'da AGENT This invention relates to crushing equipment, and particularly to an improved fastening arrangement for fastening the teeth or crushing elements of a roll crusher to the rotor of the crusher.

The invention will be described hereinafter with reference to a single-roll crusher `equipped with bars which partly project from the rotor of the crusher and fracture large pieces of rock and the like by their sledging action, but it is not limited to the specific type of` roll crusher.

lt is conventional to secure the crushing elements to the rotor by means of threaded bolts or screws whose heads are recessed in the elements. However, the bolts are subjected to stresses which they are ill equipped to withstand, and which are due partly to centrifugal stresses and partly to thenormal working stresses of crusher impact on the material to be fractured.

It has also been proposed to give the radially inner ends of the crushing elements dovetail shape for conforming engagement with a dovetail-shaped axial groove in the roller surface. The wear of the rear faces of the elements and of the cooperating backing walls of the rotor is severe in this arrangement. Also, it is inconvenient to insert the crusher elements into the rotor by axial movement into the dovetail grooves, making it difficult to replace the crushing elements.

An object of this invention is the provision of a rotor arrangement in acrusher of the type described in which the crushing elements are secured to the rotor in such a manner that there is no relative movement of the elements and the rotor during normal Crusher operation, yet the elements may be released without otherwise disassembling the rotor.

With these and other objects in view, the invention provides the rotor with a plurality of axially elongated grooves which are open in a radially outward direction. The crushing ele ments are elongated and partly received in respective grooves. A wedge element is provided in each groove for securing an associated crushing element against movement relative to the roller. For further securing the crushing element, several pins are spaced along the length of the element and are elongated transversely of the direction of elongation of the associated element, and substantially tangentially relative to the rotor axis. They hold a radially extending face of the element in abutting engagement with a radially extending wall of the associated groove.

Other features, additional objects, and many of the attendant advantages of this invention will readily become apparent from the following detailed description of preferred embodiments when considered in connection with the appended drawing which shows only as much of an otherwise conventional one-roll crusher as is needed for an understanding of the invention.

In the drawing:

FIG. ll shows the rotor arrangement of a Crusher of the invention in radial section;

FIG. 2 illustrates a modified rotor arrangement in fragmentary radial section;

FIG. 3 shows the rotor of FIG. 1 and` 2 without its crushing elements in a perspective view; and

FIG. l shows one of the crushing elements of the rotor of i FIGS. l and 3 in a perspective view, partly in radial section, and on a scale larger than that of FIG. 3.

Referring now to the drawing in detail, and initially to FIG. l, there is seen the rotor or roll of a single-roll crusher, not otherwise shown. The rotor is normally keyed to a drive shaft omitted from the drawing, and conventional in itself. Two grooves I2 in the outer face of the rotor 10 extend over the full axial length of the rotor and are diametrically opposite each other. The rotor 10 normally is driven counterclockwise, as seen in FIG. 1. The flat bottom of each groove l2 extends in a chordal plane of the rotor, and the flat trailing wall of the groove is perpendicular to the bottom. The flat leading wall is inclined toward the trailing wall at anangle of about l0.l5 so that the groove tapers ina radially outward direction, i.e., it is of dovetailed cross section.

A crushing element I4 is partly receivedin each groove and projects more beyond the leading wall of the groove l2 than beyond the trailing wall. The crushing element has the overall shape of an elongated, rectangular bar, as is also seenin FIG. 4. In the illustrated operative position of FIG. I\,the element is radially offset from the groove bottomi in an out-ward direction and held in position by a prismatic wedge I6 of trapezoidal cross section which is as long as the element 14 andcon `formingly fills thetspace between the leading wall of the groove l2 and the leading faceof the element I4. Relative radial movement of the wedge 16 and the crushing element 14 is prevented by a key i8 whichis a round rod ofmild steel simultaneously received in semicylindrical grooves of the abuttingly engaged faces of the wedge and ofthe crushing element.

Amately tangentiallyrelative to a commonrcylinderabout lthe axis of rotation. As is better seen in FIG. 4l, the cmshing element 14 is formed .with as many radially elongatedslots 22 of T-shaped crosssection as there are pins or bolts 20, only two slots 22 being visible in FIG. 4. The flange part of the slot, that is, that part of the slot which forms theflange of the T in the cross section of the slot is axial or practicallyparallel to the trailing face ofthe crushing element 14 and to the trailing face of the groove l2 which abuttingly engages the corresponding face of the element in area contact.

The web part of the slot 22 extends in a chordal plane and is perpendicular to the trailing face of the crushing element. It partly receives the stem of the bolt 20 whereasthe square head of the bolt is received in the flange part of the slot 22, the dimension of the slot longitudinally ofthe element I4 being g only slightly greater than one side of the bolt head to prevent rotation ofthe bolt.

As is best seen in FIG. 3, the rotor 10 is formed with open slots 23 which communicate with groove l2 in the trailing wall ofthe latter and receive the remainder of the stem portion of a respective bolt 20. An enlarged portion of each slot 23 receives the free end of the associated bolt 20 and a nut 21 on the bolt. The tightened nuts 2li normally hold the trailing face of the crushing element 14 in fixed engagement with the trail' ingwall of the groove `l2. The restraint of the bolts 20 is sufficient to prevent the crushing element lllfrom moving away from thegroove wall.

When it is desired to mount crushing elements in the bare rotor, as shown in FIG. 3, the wedge `It carrying the key 18 is placed on thebottom of the groove `ll2'against the leading wall. The bolts 20 are slipped into `the slots 22, `and the element 14 is inserted into the groove l2 while theA stems of the bolts enter the slots 23. The widthof the groove at the` bottom is sufficient so that the element 114i may clear the key ll which projects from the wedge I6.

The wedge 16 and element lld are then moved toward each other until the key I8 engages the semicylindrical groove in theleading face of the crushing element, and the wedge and crushing element are thereafter moved jointly in a radially outward direction into the position seen in FIG.` ll in which they are temporarily held by a wedge or by shims, not shown. When the rotor is turned thereafter atits normal` operating speed, centrifugal forces drive the connected .i wedge .and crushing element outwardly of the groove 1l2 until they are firmly clamped between the opposite walls of the groove. The nuts 2l are thereafter placed on the free ends of the bolts 20 and tightened. The temporary shms or wedges may -be removed.

In the modified embodiment illustrated in FIG: 2,the crushing elements 20 have the same external contigurationas the elements 20 described above, and are mounted on a rotor 10 identical with that shown in FIGS. lland. Awedge I6 and an associated key hold each element in position in its groove.

The element 20' has as many tangential bores as `.there are bolts 20', and the orifices of the boresl in the leading face of the crushing element are slightly enlarged to receive the flat heads of the bolts 20' otherwise similar to the `aforedescribed bolts 20. The orifices of the bores and the bolt heads recessed therein are protected by the wedge 16 which largely covers the orifice. The rotor arrangement shown in FlG. 2 is assembled in a manner obvious from the above description of FIGS. 1, 2, and 4.

For disassembling the arrangements of FIGS. l and 2, the nuts 2l are loosened, and a hammer blow on the outer face of the element 20, '0 thereafter drives the element together with the wedge 16 toward the bottom of the groove l2 until the key 18 may be disengaged from the element 14 or the wedge 16, thereby permitting the element to be withdrawn from the groove 12 in a radial direction.

It should be understood, of course, that the foregoing disclosure relates only to preferred embodiments of the invention, and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is:

1, [n a crusher comprising a rotor mounted for rotation about an axis, a plurality of crushing elements projecting outwardly of theperiphery of the rotor and disposed in axially elongated grooves extending lengthwise in the rotor periphery, each of the grooves being of dovetailed cross section having one elongated wall extending in a chordal plane of the rotor and another elongated wall tapering in an outward direction, each crushing element having a first face in abutting engagement with the one elongated wall of the groove wherein it is disposed and a second face opposite and substantially parallel thereto, a plurality of pin members fastening each of said crushing elements to the rotor, the pin members holding the first face of each crushing element in the abutting engagement with the one elongated wall of the groove wherein it is disposed, and wedge means interposed between the opposite face of each crushing element and the tapering wall of the groove wherein it is disposed, the improvement of each wedge means comprising a prismatic wedge member extending the length of the second face of the crushing element and the tapering wall of the groove and having opposite walls in abutting engagement with said second face and tapering wall, respectively, and key means locking the wedge member to the crushing element into a unit for joint movement in said outward direction.

2. 1n a crusher as set forth in claim 1, said element being formed with a radially elongated slot substantially T-shaped in cross section and open in a radially inward direction, said slot having a web part open toward said face and a flange part substantially parallel to said face, one of said pin members having a head portion received in said flange part and a stem portion partly received in said web part.

3. In a crusher as set forth in claim 2, said rotor being formed with a radially open slot, said stem portion being partly received in said slot, and securing means securing said pin member against longitudinal movement in said slot of the rotOi'.

4. In the crusher of claim l, the key means being mounted in cooperating grooves in the second wall of the crushing element and one ofthe opposite walls of the wedge member.

5. In the crusher of claim l, the crushing element being formed with a plurality of bores receiving the pin members, each bore having an enlarged orificeremote from the first face of the crushing element and at least partly covered by the wedge member, and each pin member having a head portion received in the orifice and a stem portion extending from the head portion through the first face and into the one wall of the groove. 

1. In a crusher comprising a rotor mounted for rotation about an axis, a plurality of crushing elements projecting outwardly of the periphery of the rotor and disposed in axially elongated grooves extending lengthwise in the rotor periphery, each of the grooves being of dovetailed cross section having one elongated wall extending in a chordal plane of the rotor and another elongated wall tapering in an outward direction, each crushing element having a first face in abutting engagement with the one elongated wall of the groove wherein it is disposed and a second face opposite and substantially parallel thereto, a plurality of pin members fastening each of said crushing elements to the rotor, the pin members holding the first face of each crushing element in the abutting engagement with the one elongated wall of the groove wherein it is disposed, and wedge means interposed between the opposite face of each crushing element and the tapering wall of the groove wherein it is disposed, the improvement of each wedge means comprising a prismatic wedge member extending the length of the second face of the crushing element and the tapering wall of the groove and having opposite walls in abutting engagement with said second face and tapering wall, respectively, and key means locking the wedge member to the crushing element into a unit for joint movement in said outward direction.
 2. In a crusher as set forth in claim 1, said element being formed with a radially elongated slot substantially T-shAped in cross section and open in a radially inward direction, said slot having a web part open toward said face and a flange part substantially parallel to said face, one of said pin members having a head portion received in said flange part and a stem portion partly received in said web part.
 3. In a crusher as set forth in claim 2, said rotor being formed with a radially open slot, said stem portion being partly received in said slot, and securing means securing said pin member against longitudinal movement in said slot of the rotor.
 4. In the crusher of claim 1, the key means being mounted in cooperating grooves in the second wall of the crushing element and one of the opposite walls of the wedge member.
 5. In the crusher of claim 1, the crushing element being formed with a plurality of bores receiving the pin members, each bore having an enlarged orifice remote from the first face of the crushing element and at least partly covered by the wedge member, and each pin member having a head portion received in the orifice and a stem portion extending from the head portion through the first face and into the one wall of the groove. 